Norethisterone

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vitro

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
Norethisterone and its ester derivates (norethisterone enanthate/acetate) are well-known drug substances and constituents of numerous approved drug products which have been in therapeutic use for many decades and therefore the formal data gap is more than compensated by the vast amount of clinical experience gained in their continued and widespread therapeutic use.
Overall there is proven broad exposure related to the therapeutic topical use of norethisterone related substances in transdermal therapeutic systems and there is only one isolated positive patch test reaction of unclear relevance published, compared to the substantial therapeutic use in postmenopausal patients.
Therefore based on the available reliable and relevant human data the assessment of the skin sensitization potential (hazard identification) is possible. Based on all available data there is no evidence of skin sensitization properties of norethisterone and structurally related substances.